The Didache is an ancient Christian document, believed to have been written between the first and third centuries A.D. It is a guide to Christian living, providing instruction on how to live a life of faith and holiness. The Didache covers topics
From Wikipedia
The Didache, also known as The Lord's Teaching Through the Twelve Apostles to the Nations, is a brief anonymous early Christian treatise written in Koine Greek, dated by modern scholars to the first or second century AD.